Kawi2strokes.com Forum http://www.kawi2strokes.com/forum/ |
|
Another Noob question-----1973 H1 flat in the middle throtle http://www.kawi2strokes.com/forum/viewtopic.php?f=14&t=4233 |
Page 1 of 3 |
Author: | wavehog33 [ Fri Aug 24, 2012 7:36 pm ] |
Post subject: | Another Noob question-----1973 H1 flat in the middle throtle |
I am trying to get my rebuilt/restored 1973 H1 to be all it should. I am having trouble where the bike is flat in the revs in the middle throttle and very difficult to get to run on the top. Bike starts perfect and idles like a dream. Off the pilot jet it falls flat, almost like it is loading up on fuel and not at all crisp. I have MotoGpworks chambers and my carbs are stock set except for the 95 mains. Float is set around 27-28mm (stock shows 24mm). I checked my timing with the marks and with the light and it is dead on at 4000rpm. Did a plug chop and my right and left plugs look good, right slightly lean. I replaced the plug caps with NGK resistor caps and I am running B9ES plugs. Are the resistor caps a problem?? Manual says they could be a problem?? I am also running the stock air box with a new OEM rubber boot and a new K&N filter that is oiled with No Toil spray. The carbs on the bike were pretty corroded from sitting, slides were stuck and difficult to get out. I tore them all the way down, soda bottle blasted them and then ultrasonic cleaned each carb. I then used new SUDCO kits in each. I had to wet sand the throttle slide bores to free the slides from hanging. The left side carb is the worst of the 3 as far as corrosion. When I feel each exhaust tip for pressure at idle I swear the left side cyl is "popping" harder but slower than the middle and right? Even though the timing light flashes equal on each cyl and all the marks line as they should. 1. Are the resistor caps a problem?? 2. could the condition of the the left side carb be causing the fuel not to atomize correctly resulting a slower fire even though I appear to have equal spark? 3. Possible that my coils are not putting out full juice? Thanks again...this thing has me puzzled?? My 75 Suzuki GT380 is so crisp and responsive I know this Kawi should be too. ![]() ![]() |
Author: | mraxl [ Fri Aug 24, 2012 8:03 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
You have done many things wrong... plugs should be B9HS no resistor caps set float height per spec needle & jets in carb kits are crap... put the originals back in mains are too small reclean carbs all slides should snap back without resistance... sometimes switching slides with bodies will help http://www.3cyl.com/mraxl/manuals/carbtune/carbtune.htm |
Author: | Ja-Moo [ Fri Aug 24, 2012 8:33 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
Follow Dale's advise. And the Kawi 500s didn't have a lot of low end power, the "hit" is around 6000 rpm, most chambers makes things worse, so don't expect low to mid power to be like the Suzuki. |
Author: | Looney Cylinders [ Fri Aug 24, 2012 8:42 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
B9ES plugs are long reach plugs. Hopefully you haven't started to hole your pistons ![]() ![]() J |
Author: | wavehog33 [ Fri Aug 24, 2012 8:46 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
mraxl wrote: You have done many things wrong... plugs should be B9HS no resistor caps set float height per spec needle & jets in carb kits are crap... put the originals back in mains are too small reclean carbs all slides should snap back without resistance... sometimes switching slides with bodies will help http://www.3cyl.com/mraxl/manuals/carbtune/carbtune.htm My mistake...I mis-typed. My plugs are B9HS. The carb needles are stock. When you say put originals jets back in are you meaning OEM because the originals were destroyed/corroded and plugged. The originals (OEM) were not servicable. My book shows 92.5 for the main and that is what was in the each carb before tear down. I first had 102.5 in it but just seemed to rich so I went to 95, Should I go back to the 102.5? I will re-set the floats to 24mm. Would the resistor caps make such a big difference?? Don't get me wrong, I am switching to non-resistor type but is that small potato stuff? Thanks again. The earlier help with my oil pump was great, oil pump is good to go now. |
Author: | wavehog33 [ Fri Aug 24, 2012 8:48 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
Looney Cylinders wrote: B9ES plugs are long reach plugs. Hopefully you haven't started to hole your pistons ![]() ![]() J I thought about resetting the timing too. I have never played the timing, just set to the book. As you know it is a CDI, so to get 25 degree, without using a dial gauge, what is the best way to measure? and do I move the pickups clockwise or counter? Thanks |
Author: | mraxl [ Fri Aug 24, 2012 9:24 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
wavehog33 wrote: My mistake...I mis-typed. My plugs are B9HS. The carb needles are stock. When you say put originals jets back in are you meaning OEM because the originals were destroyed/corroded and plugged. The originals (OEM) were not serviceable. My book shows 92.5 for the main and that is what was in the each carb before tear down. I first had 102.5 in it but just seemed to rich so I went to 95, Should I go back to the 102.5? I will re-set the floats to 24mm. Would the resistor caps make such a big difference?? Don't get me wrong, I am switching to non-resistor type but is that small potato stuff? Thanks again. The earlier help with my oil pump was great, oil pump is good to go now. I meant do not use kit jets or needles. Use only genuine Mikuni. Stock jet size would be fine if you had stock exhaust and air system. when you make changes to them, you have to make jetting changes to accommodate. Not doing so can result in severe engine damage. No one can tell you what size jets you need to use... That depends on altitude, air, pipes, filters. Follow the procedure in the link provided.... start rich, work down 2 sizes at a time, then back up 1 size.... after pilot & needle are set right. "is that small potato stuff?", well, that's a matter of opinion. If you want the full potential of what the CDI has to offer with fewer complications then get rid of the resistor caps.... if that isn't important to you then run what you have and keep your fingers crossed suffering the consequences. Most H1's will run best at 25 deg timing. 23 deg will work and sometimes it is best to use 24deg. There is no way to make a timing change without having the means to determine piston position. Making timing changes can mean that jetting changes need to be made to coincide. For the best likely performance, set timing at 25deg before attempting jetting. If you jet for 23 deg, it should run fine... maybe not as well as it could. But, if you jet there, it may need to be rejetted if you later decide to change timing. A word about ultra sonic cleaning.... it can be decent or it can be poor. It depends on the power and frequency used AND the cleaning solution used. The condition of the carb to begin with is also a factor. All that crud in the bottom of the bowl is also in the tiny ports within the carb body. In my mind, dipping overnite, fully disassembled, in Berryman's carb cleaner (or equivalent) followed with running a wire though each and every port and blowing out with compressed air is the only way to clean a carb that has set for years. |
Author: | Looney Cylinders [ Sat Aug 25, 2012 1:11 am ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
wavehog33 wrote: Looney Cylinders wrote: B9ES plugs are long reach plugs. Hopefully you haven't started to hole your pistons ![]() ![]() J I thought about resetting the timing too. I have never played the timing, just set to the book. As you know it is a CDI, so to get 25 degree, without using a dial gauge, what is the best way to measure? and do I move the pickups clockwise or counter? Thanks Do you have a dial caliper? If so you can use the probe in the end to establish a piston position 3.45mm BTDC. You can also make a piston stop and use a degree wheel to establish TDC, (rotate the crank in each direction until it hits the stop, note the readings and TDC is half the difference of the "lost travel") remove the stop, set the crank at your calculated TDC and then back up the crank to 25 degrees. The pickups will likely have to be moved clockwise (against crank rotation) to advance the timing from the stock setting. Ignition timing has a drastic effect on jetting. Generally the more advanced the timing the more fuel is needed to maintain a correct mixture. Low end and mid range power are much better with the advanced timing setting of 25 degrees. J |
Author: | wavehog33 [ Sat Aug 25, 2012 2:10 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
I stopped at a local performance shop to ask them some timing questions. He let me use their Snap On brand adjustable timing light. The light has a dial on the front to adjust the degrees advanced to set the ignition. Has anyone used one of these in the past? Sounds as easy as dialing the light to 25 degrees advanced, then shooting the cdi for the marks again. Then simply adjust the pickup coils on the CDI to align the mark for each cyl with the pointer. Can it really be this simple? The tool is a Snap On brand so it is not some Chinese crap that I wouldnt trust. Thanks! ![]() ![]() |
Author: | Ja-Moo [ Sat Aug 25, 2012 11:21 pm ] |
Post subject: | Re: Another Noob question-----1973 H1 flat in the middle thr |
You are over complicating things. You HAVE to find 3.45mm (or whatever you are using) and set the marker. The rest is using a timing light at above 4000rpm and move the pick up until it's aligned. One problem, is auto timing light can't keep up with 2 stroke, because they fire every revolution. Do not use the advance adjustment on the timing light. |
Page 1 of 3 | All times are UTC - 5 hours |
Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |